Description of Test
This was a slightly modified version of the Ravens Matrices test that was used in the 12 Year study. In this 14 Year version, the final sub-test (F) was extended to include the even-numbered as well as the odd-numbered items: an increase in length of 6 items. In other respects, the test was unchanged from the 12 Year version.
This test consisted of a series of incomplete patterns ("matrices"); in each case, the twin was asked to identify the missing part of the pattern. The twin did this by clicking on one of 8 possible missing parts. The patterns and missing parts are shown in full in the table of test items below.
The test comprises 4 sub-tests or sections, labelled C, D, E and F. Sub-tests C, D and E each consist of 6 items, numbered 1, 3, 5, 7, 9 and 11 (even-numbered items from the original version of the test were dropped); sub-test F consists of all 12 original items (numbered 1 to 12). Hence there are 30 items in total. A twin may have been presented with fewer than 30 items, because of the discontinue rule (described below). The sub-tests were presented in sequence: C then D then E then F. The discontinue rule applies independently within each sub-test, as described below.
Test Rules
- Scoring
For each question, the correct response is given a score of 1, and any of the 7 incorrect responses is given a score of 0. The maximum total score for the test is 30. - Ordering of items
The 4 sub-tests are presented in sequence: C then D then E then F. Within each sub-test, items are presented in increasing numerical order of item number, subject to the discontinue rule below. - Discontinue rule
- Start with the first three items in the sub-test
(items 1, 3 and 5 for sub-tests C, D and E; items 1, 2 and 3 for sub-test F) - If the first three items are all incorrect, discontinue the sub-test (skip the remaining items). Move on to the next sub-test (or if in sub-test F, end the test).
- If at least one of the first three items is correct, proceed with the remaining items of the sub-test, in numeric order. Then move on to the next sub-test (or if in sub-test F, end the test).
- Start with the first three items in the sub-test
- Timeout rule
There is no special timeout rule for this test, so the default timeout of 5 minutes applies to each item. See the summary of 14 Year web tests for more details.
Item Variables
The item variables relating to the Raven's test, as listed in the table below, were generated automatically by programs on the web server during the course of the test. Note that the dataset only includes data for completed tests. If a twin started the test but left it unfinished, then the data for the test were not used. Note that the variable holding the total test score was also generated automatically on the web server. It is therefore treated as an item variable (it did not have to be derived as at age 10).
In most cases the values of these variables have been left unaltered, although some have been recoded during data cleaning as follows. See the web data cleaning page for further details.
- For timed out items, the item response variable is recoded from missing to -1, and the item answer time is recoded to missing (item scores are 0)
- For items skipped due to the discontinue rule, the item response variable is recoded from missing to -2, and the item score is recoded from missing to 0.
- For items that were interrupted, crashed or malfunctioned in any way, the item response variable is recoded from missing to -4, and the item score is recoded from missing to 0.
- For instances of tests compromised by excessive loss of data, the status flag is recoded from 2 to 3, the data flag is recoded from 1 to 0, and all item variables are recoded to missing (test data deleted)
- For twins identified as random responders in this test, the status flag is recoded from 2 to 4, the data flag is recoded from 1 to 0, and all item variables are recoded to missing (test data deleted)
The test start and end dates and times, and item answer and download times, have not been retained in the dataset.
| Variables | Explanation | Values |
|---|---|---|
| nrvdata1/2 | Data flag: was this test completed? | 0=no, 1=yes |
| nrvstat1/2 | Test status: outcome of test | 0=not started, 1=started but not finished, 2=successfully completed, 3=test compromised by loss of data, 4=random responses |
| nrvtot1/2 | Total score for this test, out of 30. | 0 to 30 (integer values) |
| nrvstdt1/2 | Start date of the test [not in dataset] | Date values |
| nrvsttm1/2 | Start time of the test [not in dataset] | Time values |
| nrvendt1/2 | End date of the test [not in dataset] | Date values |
| nrventm1/2 | End time of the test [not in dataset] | Time values |
| nrvsess1/2 | Number of sessions (at the computer) used by the twin to complete the test. | Integer values of 1 or above |
| nrvtime1/2 | Time taken to complete the test, in seconds | Integer values (number of seconds) |
| nrXYYan1/2 * | Item response (picture number selected, as tabulated below) | 1 to 8 (integer values) |
| nrXYYsc1/2 * | Item score (see table of items below for details) | 0=incorrect, 1=correct |
| nrXYYat1/2 * | Answer time: length of time (in seconds) taken by the twin to respond to this item [not in dataset] | Integer values (number of seconds) |
| nrXYYdt1/2 * | Download time: length of time (in seconds) between the end of the previous item and the start of this item; time needed to download files for this item [not in dataset] | Integer values (number of seconds) |
* XYY denotes the item: X is the sub-test (c, d, e or f), and YY is the item number within the sub-test (01 to 12, odd numbers only for sub-tests c, d and e).
Test Items
The numbering of the items, shown in the table below, equates to the numbering used in the item variables. The order in which items are presented in this table is the same as the order in which items are presented to the twins in the test, subject to the discontinue rule (see test rules above).
| item | correct response | picture |
|---|---|---|
| C1 | 8 |  |
| C3 | 3 |  |
| C5 | 7 |  |
| C7 | 5 |  |
| C9 | 7 |  |
| C11 | 1 |  |
| D1 | 3 |  |
| D3 | 3 |  |
| D5 | 8 |  |
| D7 | 5 |  |
| D9 | 1 |  |
| D11 | 5 |  |
| E1 | 7 |  |
| E3 | 8 |  |
| E5 | 1 |  |
| E7 | 1 |  |
| E9 | 3 |  |
| E11 | 4 |  |
| F1 | 7 |  |
| F2 | 2 |  |
| F3 | 7 |  |
| F4 | 5 |  |
| F5 | 6 |  |
| F6 | 5 |  |
| F7 | 4 |  |
| F8 | 8 |  |
| F9 | 5 |  |
| F10 | 1 |  |
| F11 | 3 |  |
| F12 | 2 |  |